In order to investigate the effect of thermal sterilization on the characteristics of Cili(Rosa roxburghii)wine,Cili wine was treated at 60,65,and 70℃ for 15 min and then stored at room temperature with untreated Cil...In order to investigate the effect of thermal sterilization on the characteristics of Cili(Rosa roxburghii)wine,Cili wine was treated at 60,65,and 70℃ for 15 min and then stored at room temperature with untreated Cili wine as the control(CK stored at 4℃).After six months,the sterilization effect,turbidity,pH value,alcohol content,volatile acidity,titratable acidity,total sugar,and vitamin C were determined.The volatile components in all the wine samples were extracted via head-space solid-phase microextraction(HS-SPME)and identified by gas chromatography-mass spectrometry(GC-MS).Thermal treatment at 60~70℃ completely eliminated the microorganisms in Cili wine and had no significant effect on turbidity,pH value,alcohol content,volatile acidity,or vitamin C.The treatment brought increment in titratable acidity and decrement in total sugar compared with the CK.In particular,the treatment at 70℃ increased the number of volatile compounds to 34 compared with the CK(30).The results suggested that Cili wine sterilized at 60~70℃ water bath can keep good quality without deterioration for 6months at room temperature.展开更多
An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus （S. aureus）. The plasma jet was generated by dielectric barrier discharge （DBD）, which was characterized by electrical ...An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus （S. aureus）. The plasma jet was generated by dielectric barrier discharge （DBD）, which was characterized by electrical and optical diagnostics. The survival curves of the bacteria showed that the plasma jet could effectively inactivate 10 6 cells of S. aureus within 120 seconds and the sterilizing efficiency depended critically on the discharge parameter of the applied voltage. It was further confirmed by scanning electron microscopy （SEM） that the cell morphology was seriously damaged by the plasma treatment. The plasma sterilization mechanism of S. aureus was attributed to the active species of OH, N 2 ＋ and O, which were generated abundantly in the plasma jet and characterized by OES. Our findings suggest a convenient and low-cost way for sterilization and inactivation of bacteria.展开更多
Air sanitization acquired renewed interest during the COVID-19 outbreak, especially in hospital rooms and intensive care units. In this work, mathematical analysis was done of the convenience of sanitizing the air of ...Air sanitization acquired renewed interest during the COVID-19 outbreak, especially in hospital rooms and intensive care units. In this work, mathematical analysis was done of the convenience of sanitizing the air of whole rooms or personalized isolation tents. Centralized air sanitization was found to have low effectiveness due to three reasons: 1) the constant virus emission from patients;2) the practical upper limits of air recycle flowrates;3) the low value of the minimum infective dose of SARS-CoV-2. Personalized air sanitization was the best option. Virus inactivation by thermal effect was then revisited, and a steady-state model was formulated for an efficient and personalized thermal sterilizer. An analytical solution was obtained for temperature and virus concentration in different parts of the sterilizer. Cell temperature was found to be the main variable for sterilization due to the Arrhenius-like form of the kinetic constant of virus deactivation. An objective cost function was written and subjected to conditions of minimum patient ventilation rate and minimum virus removal effectiveness. Numerical optimization gave an optimal design with the intrinsic advantages of thermal sanitization, i.e., simplicity, robustness, minimum maintenance and high sanitization rate.展开更多
文摘In order to investigate the effect of thermal sterilization on the characteristics of Cili(Rosa roxburghii)wine,Cili wine was treated at 60,65,and 70℃ for 15 min and then stored at room temperature with untreated Cili wine as the control(CK stored at 4℃).After six months,the sterilization effect,turbidity,pH value,alcohol content,volatile acidity,titratable acidity,total sugar,and vitamin C were determined.The volatile components in all the wine samples were extracted via head-space solid-phase microextraction(HS-SPME)and identified by gas chromatography-mass spectrometry(GC-MS).Thermal treatment at 60~70℃ completely eliminated the microorganisms in Cili wine and had no significant effect on turbidity,pH value,alcohol content,volatile acidity,or vitamin C.The treatment brought increment in titratable acidity and decrement in total sugar compared with the CK.In particular,the treatment at 70℃ increased the number of volatile compounds to 34 compared with the CK(30).The results suggested that Cili wine sterilized at 60~70℃ water bath can keep good quality without deterioration for 6months at room temperature.
基金supported by National Natural Science Foundation of China (Nos.10835004 and 10905010)the New Century Excellent Talents in University of China (No.NCET-08-0760)
文摘An atmospheric non-thermal plasma jet was developed for sterilizing the Staphylococcus aureus （S. aureus）. The plasma jet was generated by dielectric barrier discharge （DBD）, which was characterized by electrical and optical diagnostics. The survival curves of the bacteria showed that the plasma jet could effectively inactivate 10 6 cells of S. aureus within 120 seconds and the sterilizing efficiency depended critically on the discharge parameter of the applied voltage. It was further confirmed by scanning electron microscopy （SEM） that the cell morphology was seriously damaged by the plasma treatment. The plasma sterilization mechanism of S. aureus was attributed to the active species of OH, N 2 ＋ and O, which were generated abundantly in the plasma jet and characterized by OES. Our findings suggest a convenient and low-cost way for sterilization and inactivation of bacteria.
文摘Air sanitization acquired renewed interest during the COVID-19 outbreak, especially in hospital rooms and intensive care units. In this work, mathematical analysis was done of the convenience of sanitizing the air of whole rooms or personalized isolation tents. Centralized air sanitization was found to have low effectiveness due to three reasons: 1) the constant virus emission from patients;2) the practical upper limits of air recycle flowrates;3) the low value of the minimum infective dose of SARS-CoV-2. Personalized air sanitization was the best option. Virus inactivation by thermal effect was then revisited, and a steady-state model was formulated for an efficient and personalized thermal sterilizer. An analytical solution was obtained for temperature and virus concentration in different parts of the sterilizer. Cell temperature was found to be the main variable for sterilization due to the Arrhenius-like form of the kinetic constant of virus deactivation. An objective cost function was written and subjected to conditions of minimum patient ventilation rate and minimum virus removal effectiveness. Numerical optimization gave an optimal design with the intrinsic advantages of thermal sanitization, i.e., simplicity, robustness, minimum maintenance and high sanitization rate.
